Fuse retainer and extractor

ABSTRACT

A fuse holder constructed from a dielectric material which is also elastic or partly elastic, such as plastic, formed to provide a cylinder split longitudinally and chamfered at either end to receive a cartridge fuse, such cylinder having attached thereto a handle to facilitate grasping of the fuse holder. At the distal ends, the handle extends to form insulating chambers partly surrounding the respective connector end caps of the fuse and opening along one lateral surface thereof to receive the corresponding spring clips of a fuse clip. The distally opposite surfaces of the respective housings are pierced to form openings concentric with the axis of the cylinder, said openings being sized to pass the fuse into the interior cavity of the cylinder. In another embodiment, the handle is formed to provide a second fuse holder substantially shaped in a similar manner as the first fuse holder, for holding a spare fuse for replacement.

United States Patent 1191 'Cetola et a1.

111 3,813,626 May 28, 1974 FUSE RETA INER AND EXTRACTOR Inventors: HenryA. Cetola, Yorba Linda;

Timothy J. Crosby, Anaheim, both of Calif.

Robertshaw Controls Company, Richmond, Va.

Filed: Dec. 15, 1972 Appl. No.: 315,323

Assignee:

US. Cl. 337/245, 174/138 F, 174/138 G, 337/186, 337/213, 337/215,337/264 Int. Cl. H0lh 85/14 Field of Search 337/186, 194, 215, 245,337/202, 209, 138,213,264; 174/138 G,

References Cited I UNITED STATES PATENTS FOREIGN PATENTS ORAPPLICATIONS;

6/1941 Fenske et al....

18,276 8/1914 Great Britain 337/245 1,109,610 9/1955 France ..337/2643/1955 Australia....; 337/245 11/1935 Baker ..337/245x 3/1966 Melia174/138 G Primary Examiner-Bernard A. Gilheany Assistant Examiner-FredE. Bell A Attorney, Agent, or FirmFulwider, Patton, Rieber, Lee & Utecht[57] ABSTRACT A fuse holder constructed from a dielectric material whichis also elastic or partly elastic, such as plastic, formed to provide acylinder split longitudinally and chamfered at either end to receive acartridge fuse, such cylinder having attached thereto a handle tofacilitate grasping of the fuse holder. At the distal ends, the handleextends to form insulating chambers partly surrounding the respectiveconnector end caps of the fuse and opening along one lateral surfacethereof to receive the corresponding spring clips of a fuse clip. Thedistally opposite surfaces of the respective housings are pierced toform openings concentric with the axis of the cylinder, said openingsbeing sized topass the fuse into the interior cavity of the cylinder. Inanother embodiment, the handle is'formed to provide a second fuse holdersubstantially shaped in a similar manner as the first fuse holder, forholding a spare fuse for replacement.

I 9 Claims, 5 Drawing Figures PATENTEDIM 2a 1914 Pam FIG..2

l FUSE RETAINER AND EXTRACTOR I BACKGROUND OF THE INVENTION 1. Field ofthe Invention The present invention relates to fuse holders, and moreparticularly to fuse holders adapted to receive fuses of thecartridgetype for a manual installation and extraction thereof in correspondingfuse clips.

2. Description of the Prior Art In the electrical art it has been thecommon practice to provide fuse protection to various elements of acircuit in order to insure that any current overload in the circuit willfirst destroy the fuse, thereby opening the circuit and protecting othermore critical or expensive items on the line. Very often such criticalcomponents are designed to operate at different power levels, thus calcircuit. Furthermore, very often such circuits include a plurality ofcircuit elements drawing in parallel power from a common power sourceand separate fuse protection of each circuit element is required inorder to limit the element to a safe current load. Thus, it has been thegeneral practice in the prior art to provide a plurality of fuses inany-one circuit, conveniently located in one centralized location, forprotection and diagnosis. Physical space considerations, particularly incircuits having a large number of circuit elements and therefore a largenumber of fuses, often dictates small fuse dimensions, and for suchapplications, fuses of the cartridge type have had most prevailingapplication. Such cartridge fuses generally comprise an insulator tubeclosed at both ends by conductive end caps, having disposed therebetweena fuse bus connecting the end caps. The end caps engage respective fuseclips connected to the ends of respective leads. In this manner, thefuse closes the circuit betweenthe respective end clips and upon removalthereof at least one of the end clips is usually energized, presenting ahazard of shock and injury to the manual installer. Thus, there havebeen many prior art devices developed in the past which are specificallyadapted to provide a means for insulated manual grasping of thecartridge fuse without unnecessarily exposing the installer to shockhazard. Heretofore, all such devices provided extensions or handles bywhich the cartridge fuse could be grasped without providing anyinsulation or protection between the installer and the exposed clips,thus presenting a hazard of shock and shorting across the adjacent clipsduring installation. Since most usually when a fuse is removed it is fordiagnosis purposes, it is generally desirable to have in convenientarrangement a replace ment fuse of the same rating and dimensions toreplace the removed fuse if such fuse appears to have burned out.Heretofore, the prior art devices generally did not provide such areplacement, thus requiring that the installer carry an inventory ofassorted fuses for replacement.

SUMMARY OF THE INVENTION staller from the exposed terminals of the fuseclips.

Other objects of the invention are to provide within the 2 generalconfines or dimensions of the fuse holder, a second or replacement fusedisposed for immediate insertion in the fuse clip.

Briefly these and other objects are accomplished within the presentinvention by forming of a resilient or partly resilient material havinghigh dielectricor insulating properties a fuse holder including a fuseholding hollow cylinder having the interior diameter-thereof confonnedto receive the-insulated portion of a standard cartridge fuse, theinterior opening being further chamfered at either end and splitlongitudinally to per mit expansion thereof, thus allowing the largerdiameter end caps to be passed therethrough. Formed along one side 'ofthe cylinder, and in longitudinal alignment therewith, is a handle formanual grasping. Formed at the distal ends thereof are end shields whichare disposed to surround the respective end caps of the fuse when suchfuse is inserted. The end shields are open at the bottom to permitinsertion of the fuse for retention thereof by fuse clips. The distallyopposed surfaces of the respective end shields are pierced to formcircular openings in concentric relationship with the central axis ofthe cylinder, the diameters thereof conforming to the largest diameterof the cartridge fuse.

In one other embodiment of the present invention, the handle has formedthereon a second cylinder, also split and chamfered to receive acartridge fuse includ- BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is aside view in partial cross section of a fuse holder embodying thepresent invention;

FIG. 2 is a bottom view of the fuse holder shown in FIG. 1;

FIG. 3 is a cross sectional view taken along line 3-3 of FIG. 2;

FIG. 4 is a side view in partial cross section of yet another embodimentof a fuse holder of the present invention; and

FIG. 5 is a cross sectional view taken along line 5-5 of FIG. 4.

DESCRIPTION OF THE PREFERRED I EMBODIMENTS As shown in FIG. I, a fuseholder 10, formed of an elastic or partly elastic material having highdielectric or insulating properties, such as plastic and the like,comprises a fuse retaining cylinder 11 enclosing a cylindrical cavity 12sized to conform with the dimensions of the insulator barrel of aconventional cartridge fuse 15. At either end the cavity 12 formschamfered annular surfaces 17 and 18 diverging at the outer edgesthereof to a diameter greater than the diameter of end caps 15 a and 15bof fuse l5. Fuse 15, at end caps 15a and 15b, is insertable intoassociated terminals or spring clips 19a and 1% attached to the mountingstructure of a conventional fuse clip 19. Formed on 3 one side ofcylinder 11, in longitudinal alignment therewith and in substantialopposing relationship with fuse clip 19 is a handle 20, shapedsubstantially as planar structure projecting radially away from cylinder11. At the free edge, and proximate the ends thereof, handle 20 expandsto form in perpendicular arrangement surfaces or lips 21 and 22 tofacilitate grasping of the fuse holder and for removal of fuse from fuseclip 19 and to provide surfaces for exerting pressure duringinstallation. At the juncture with cylinder 11 handle 20, at both endsthereof, extends to form insulator housings a and 20b, forming walls tosurround the exposed end caps of fuse l5 and opening at the surfaceadjacent fuse clip 19 to receive spring clips 19a and 19b. The distallyopposed surfaces of housings 20a and 20b are pierced to form circularopenings 23a and 23b aligned concentrically with the central axis ofcavity 12 and sized to pass fuse 15 into cavity 12.

As shown in more detail in FIGS. 2 and 3, cylinder 11 is splitlongitudinally to form a separation thereby allowing circumferentialexpansion of the cylinder to allow passage of the larger end caps offuse 15 therethrough. The respective insulator housings20a and 20b aresized substantially to accommodate the respective ends of fuse 15 andthe correspondingfuse clips (not shown in this figurelallowing forsuccessive replacement of fuses where one fuse expells the precedingfuse. In this manner, housings 20a and 20b, when installed, provideshielding in all areas at which spring clips 19a and 19b would beaccessible by the installer during installation of an adjacent fuse.

Yet another embodiment of the present invention is illustrated in FIG. 4showing a fuse holder 30 including a first and second fuse retainingcylinder 31 and 32 constructed substantially similar to cylinder 11 ofFIG. 1. Cylinders 31 and 32 extend from a central planar member 33 in asubstantially parallel alignment, where the distal ends of member 33extend to form a first and second opposed insulative shield housing 330and 33b forming opposing chambers 34a, 35a and 34b and 35b acrossrespective common walls 36a and 36b. Walls 36a and 36b form a planeacross the ends of member 33 in a substantially equidistant positionfrom the central axes of cylinders 31 and 32, separating the respectivechambers 34a and-34b and chambers 35a and 3512 from each other. v

As previously described, cylinder 31 forms a cavity 44 dimensioned toconform with the insulator barrel of a first cartridge fuse 38, therespective end caps of fuse 38 engaging spring clips 40a and 40b of aconventional fuse clip 40. Similarly, cylinder 32 encloses a spare fuse39, of a size and power rating equal to fuse 38, providing animmediately replacement available upon failure of fuse 38. The distallyopposite surfaces of chambers 34a and 34b and-chambers 35a and 35b arepierced with circular openings 41a and 41b and openings 42a and 42b eachrespectively formed in concentric alignment with the central axes of thecorresponding cylinders 31 and 32. Openings 41a and 41b and 42a and 42bare sized to pass the end caps of the fuses 38 and 39, allowing forinsertion of the fuses into cylinders 31 and 32. As shown in more detailin FIG. 5, cylinders 31 and 32 are split longitudinally to formseparations 31a and 32a, allowing the respective cylinders to expand orenlarge while passing the end caps of fuses 38 or 39. In a similarmanner to that shown in FIG. 1, the distal ends of cylinders 31 and 32are chamfered to a diameter greater than the diameter of the respectiveend caps, accommodating insertion of the fuse and expanding of therespective cylinder chambers.

In operation, the respective clinders 31 and 32 receive fuses throughthe coaxial opening formed in the distally opposed walls of the shieldhousings 33a and 33b being pressed to a position where the respectiveend caps of the fuses are exposed for insertion into the correspondingspring clips. The removal and reinsertion of any fuse can beaccomplished by any conventional tool such as a round bar (not shown) ofsufficiently small diameter to pass through the openings. Furthermore,the concentric alignment of the openings and the respective cylindersallows for a sequential replacement of successive fuses where one fuseis used to force out the previous fuse. Installation and withdrawal ofthe fuse retained in the first fuse holder is facilitated by lips orsurfaces 21 and 22 extending from the handle. Similarly, withdrawal andinstallation of fuses contained in the second fuse holder is facilitatedby the enlargements of the respective cylinders, where one cylinder canbe used as a handle to force installation or withdrawal of the fusecontained in the other cylinder.

Some of the many advantages of the present invention should now bereadily apparent. In one of its embodiments, the present inventionprovides for a fuse holder, easily manufactured or cast from any partlyelastic or elastic material, such as plastic and the like, which alsohas a high dialectric or insulative quality, providing the insulatorshielding around the exposed spring clips and thereby protecting theinstaller from shock or any possibility of shorting. Furthermore, theexpansive character of the respective cylinders of the fuse holdersallows for a relatively low accuracy method of construction such as, forexample, a casting while at the same time providing a convenient methodof installation of a cartridge fuse.

Various modifications and changes may be made with regard to theforegoing detailed description without departing from the spirit of theinvention.

What is claimed is:

l. A fuse holder for receiving cartridge fuses disposed for insertion infuse clips, comprising in combination:

a first resilient cylinder incuding a first central cavity conformed tolongitudinally receive the insulative cylinder of a first cartridgefuse;

handle means attached to said cylinder and disposed longitudinaltherewith in radial projection for providing insulative manual graspingand pressing surfaces; and

first end insulator means attached to said handle means at both endsthereof formed to partly surround the exposed ends of the first fusereceivable in said cylinder and adapted to receive correspondingterminals of a fuse clip disposed for attachment with said first fusefor providing insulative walls thereabout, said walls including openingsfor passing said first fuse into said first central cavity.

2. A fuse holder according to claim 1, wherein:

said first end insulator means is formed with an opening disposed insubstantially opposing relationship with said handle means for receivingthe terminals of said fuse clip.

3. A fuse holder according to claim 2, wherein:

said first resilient cylinder further includes annular chamfers formedin the distal ends of said first cen- 'tral cavity and diverging to adiameter greater than the end diameter of the receivable fuse at the endsurfaces of said first cylinder, and a separation formed longitudinallyin the wall of said first cylinder.

4. A fuse holder according to claim 3 wherein:

said openings further include circular apertures formed in the distallyopposed walls of said first end insulator means in concentric alignmentwith said first cylinder and of a diameter greater than the exteriordiameter of said fuse.

5. A fuse holder according to claim 4, wherein:

said handle means further includes a first insulative planar memberattached at one edge thereof to said cylinder and projecting readiallytherefrom and a second planar member attached in substantially normalalignment with said first planar member proximate the distal ends of theother edge thereof? 6. A fuse holder according to claim 2, wherein:

said handle means further includes a second resilient cylinder formed inparallel alignment with said first resilient cylinder and including asecond central cavity conformed to longitudinally receive the insulativecylinder of a second cartridge fuse and second insulator means attachedto said handle means at both ends thereof formed to surround the exposedends of the second fuse receivable in said second cylinder includingopenings on the distally '6 opposed surfaces thereof for passing saidfuse into said first and'second cavity and adapted to receivecorresponding terminals of a fuse clip in substantially opposingrelationship with said first end insulator means for providinginsulative walls thereabout.

7. A fuse holder according to claim 6, wherein:

said first and second end insulator means is formed 9. A fuse holderaccording to claim 8, wherein: said openings in said first and secondend insulator means further include circular apertures formed in thedistally opposed walls thereof in concentric alignment with said firstand second cylinders and of a diameter greater than the exteriordiameter of said fuse.

1. A fuse holder for receiving cartridge fuses disposed for insertion infuse clips, comprising in combination: a first resilient cylinderincuding a first central cavity conformed to longitudinally receive theinsulative cylinder of a first cartridge fuse; handle means attached tosaid cylinder and disposed longitudinal therewith in radial projectionfor providing insulative manual grasping and pressing surfaces; andfirst end insulator means attached to said handle means at both endsthereof formed to partly surround the exposed ends of the first fusereceivable in said cylinder and adapted to receive correspondingterminals of a fuse clip disposed for attachment with said first fusefor providing insulative walls thereabout, said walls including openingsfor passing said first fuse into said first central cavity.
 2. A fuseholder according to claim 1, wherein: said first end insulator means isformed with an opening disposed in substantially opposing relationshipwith said handle means for receiving the terminals of said fuse clip. 3.A fuse holder according to claim 2, wherein: said first resilientcylinder further includes annular chamfers formed in the distal ends ofsaid first central cavity and diverging to a diameter greater than theend diameter of the receivable fuse at the end surfaces of said firstcylinder, and a separation formed longitudinally in the wall of saidfirst cylinder.
 4. A fuse holder according to claim 3 wherein: saidopenings further include circular apertures formed in the distallyopposed walls of said first end insulator means in concentric alignmentwith said first cylinder and of a diameter greater than the exteriordiameter of said fuse.
 5. A fuse holder according to claim 4, wherein:said handle means further includes a first insulative planar memberattached at one edge thereof to said cylinder and projecting readiallytherefrom and a second planar member attached in substantially normalalignment with said first planar member proximate the distal ends of theother edge thereof.
 6. A fuse holder according to claim 2, wherein: saidhandle means further includes a second resilient cylinder formed inparallel alignment with said first resilient cylinder and including asecond central cavity conformed to longitudinally receive the insulativecylinder of a second cartridge fuse and second insulator means attachedto said handle means at both ends thereof formed to surround the exposedends of the second fuse receivable in said second cylinder includingopenings on the distally opposed surfaces thereof for passing said fuseinto said first and second cavity and adapted to receive correspondingterminals of a fuse clip in substantially opposing relationship withsaid first end insulator means for providing insulative wallsthereabout.
 7. A fuse holder according to claim 6, wherein: said firstand second end insulator means is formed with an opening disposed insubstantially opposing relationship for receiving the terminals of saidfuse clip.
 8. A fuse holder according to claim 7, wherein: said firstand second resilient cylinders further include annular chamfers formedin the distal ends of said first and second central cavities divergingto a diameter greater than the end diameter of the receivable fuse atthe end surfaces of said first and second cylinders and a separationformed longitudinally in the wall of said first and second cylinders. 9.A fuse holder according to claim 8, wherein: said openings in said firstand second end insulator means further include circular apertures formedin the distally opposed walls thereof in concentric alignment with saidfirst and second cylinders and of a diameter greater than the exteriordiameter of said fuse.